h2g2 The Hitchhiker's Guide to the Galaxy: Earth Edition

There's this little question that's been boggling my mind for a while... if you take a glass of alcohol (vodka for example), drop some ice cubes in it and put it in the freezer, then what? Will the ice cubes melt or grow bigger? This is of course assuming that the alcohol is the same temperature as the freezer (below the freezing point of water), and that this very same temperature is over the freezing point of the alcohol...

Since alcohol, mainly ethanol is soluable (missible) in water it will probably effect the melting point of water,
therefore at about -2 or -3 C the ice cubes will probably melt. I'm not sure so you should probably try it out

This is an interesting question. To me, anyway.

Ethyl alcohol, a.k.a. ethanol, is the second largest constituent in your vodka at 40% by volume - assuming you have the typical 80-proof vodka. Ethanol has a freezing point (or melting point) of -112 C. Obviously, this is quite a bit colder than your average household freezer. So your freezer will not be able to freeze the ethanol in your vodka. Vodka is particularly well-suited to this experiment as it is a very close example of a true binary system (i.e. it is almost completely made up of just two components - vodka is a neutral spirit, so it doesn't have any flavor compounds to speak of, at least not on the order of gin or whisky or [saints preserve us] Jagermeister).

As to whether or not the ice cubes will grow, I am not entirely certain. To apply the scientific method, I hypothesize that they would indeed grow eventually. Basis: Water is still the major consituent of vodka (very nearly 60% by volume for 80-proof vodka). Water freezes at 0 C. I assume most freezers maintain temperatures in the 0 to -4 C temperature range. Therefore, I think that the water in the vodka will freeze along with the ice cubes. Whether this will occur at the site of the ice cubes themselves is uncertain - using my "gut feeling" as a chemical engineer, I would *guess* that the ice will form along the top of the uncovered glass and also along the sides and bottom, perhaps with some crystals growing towards the floating ice cubes. These will likely be the places of lowest temperature - thermodynamics tells us that most heat will be lost through conduction, or phsyical contact between the glass and the already-freezing interior surface of your freezer. However, since glass is a pretty good insulator, and since your freezer actually blows cold, dry air all around, you might find that the surface of your drink will freeze if the forced convection turns out to be the major contributor to the actual heat loss, but now I'm getting needlessly pedantic.

What may be causing some confusion here is the fact that water and ethanol form an azeotropic mixture at roughly 95% ethanol and 5% water. Without going into a lenghty lecture on why that is, what it really *means* is that this particular *mixture* will boil at a temperature *different* than that of either of the pure components - in this case, about 78.15 C a little lower than that of pure ethanol. So it becomes impossible to obtain a higher concentration of ethanol (eg. 96% to 100%) by using distillation of ethanol and water alone. This is why when you buy distilled spirits, the proof is never higher than 190 proof (proof is merely twice the volume percentage of ethanol). With some difficulty, pure ethanol can be distilled using benzene to get another azeotrope at 7.5% water ... eventually pure ethanol will come over. Why one would ever want to drink anything of that strength is another mystery entirely.

Azeotropes, however, refer to the boiling points of liquid solutions, and not to freezing points. Freezing points are usually affected by ionic dissociations (like putting NaCl, or table salt, in water). Mixing two polar solvents (like water and ethanol) should not have an effect on freezing points but only on boiling points (this is due to an effect called hydrogen bonding, in case you want to look it up). Compounds with ionic bonding (like salts) are easily dissolved and dissociated in polar solvents like water, and this why adding salt to ice/snow will melt the ice/snow. It is also why sea water will not freeze at 0 C but quite frequently at -5 C or even lower in some cases. The dissolved salts "get in the way" of the freezing process and lower the freezing temperature of the water mixture. Just to be clear, that is NOT what happens with a mixture of ethanol and water.

But onward with our scientific method. I propose that putting a glass of vodka (large glass, 4-6 oz.) with ice cubes (2, floating) into your freezer overnight will result in larger ice cubes in the morning. Turning your freezer way down on it's coldest setting might help accelerate this effect. I think I'm going to further apply the scinetific method and test my theory myself tonight. I'll present my results tomorrow.

I apologize for the delay.

Here are my** results:

RE: Freezing Alcohol

Experimental parameters: One (1) common glass (6 oz.) of vodka (Smirnoff brand, 80 proof) with two (2) ice cubes (floating), placed in an ordinary household freezer for 24 hours.

Hypothesis: The ethanol in the vodka will not freeze. Further, the ice cubes will not melt. The water in the vodka will freeze, forming up on the surface or along the sides of the glass.

Summary of results: The single experiment indicated the hypothesis is correct. More tests should be performed under similar conditions for hyphothesis to become law.

Results: Upon initial observation of the glass, it appeared that it the vodka and ice had formed a giant solid 'ice cube.' In other words, that it all frozen. This inital observation was discounted by Oberserver #1 as, approximately 2 minutes later, the 'ice' had melted ... partially. It became clear, as the ice was melting, that it had been only a layer of ice formed up on the surface of the mixture. More layers of ice now became visible along the edges and bottom of the glass. There were clearly two (2) ice cubes of normal size floating in the mixture. At this point, Observer #2 proposed a taste test of the mixture to give a crude estimate of the concentration of ethanol in the mixture while some ice still remained. Observer #1 agreed, and two (2) samples were taken independently, one by each Observer. Observer #1 quickly noted a pungent taste commonly referred to as "freezer burn" which was rapidly overpowered by the strong taste of ethanol. Observer #2 was noted as saying, "ugh - this tastes like !" Observer #2 rapidly proposed and implemented a procedure for sampling a Control, namely afore mentioned vodka (conventionally chilled in refrigerator, approx. 3 oz., no ice). Observer #1 duplicated Observer #2's prudently executed maneuver. Observer #1 noted a much smoother and less alcoholic taste from the Control sample than had just been sampled from the Experimental blend. Observer #2, sadly, eliminated any option for further testing by immediately pouring the Experimental sample down the sink.

These observations support the theory that the 40% water in the vodka did indeed freeze along typical thermodynamic pathways. The ice cubes mainly helped in the formation of a thin upper ice layer in the glass (which was placed in a crowded freezer, with little or no cold air blowing across the top of the glass). The ice cubes did not melt appreciably.

An incidental discovery occured wherein it was determined that vodka frozen in this manner and thawed out later absords some sort of foul chemical found in freezers which makes many things taste ... well, foul.

Freezing vodka in an open container for later consumption is not recommended.


Observer #1: J. Nelson
Observer #2: S. Quinn

Bravo! Truly, your research qualifies as a shining example of the scientific method at work.

I brew my own wine - a couple of Christmasses ago I decided to (illegally) distill one gallon of a sweet orange wine down to one bottle of "rocket fuel" by placing the wine in a polythene container in the freezer and gradually removing the ice crystals as they formed (as alcohol does not freeze I assumed I would be left with something remarkable). As the largest container I had only held 1 pint it took some weeks to complete and the bottle was eventually ready on Christmas Eve. I was so looking forward to sampling it - I was hoping for something like Cointreau. A guest arrived - I found and polished the liqueur glasses, reached for the bottle and it blew up! I have not bothered since.

There is a knack to distilling, else it does blow up. That's one of the reasons that they made it illegal, to stop people hurting themselves on shards of flying glass. It is far bette, and safer, to heat the alcoholic mixture, stick the vapour through a condensing jacket and then ad a percentage of the original mixture back to the evaproated / codensed result to add the flavour back. As long as you get your sums right (if you don't you CAN go blind) the hardest part is getting hold of some laboratory equipment to do the distilling in.

bump

Thought this was worth saving from the last page of askh2g2 for a fresh airing.

Anyone care to carry on this obviously critical research project and make an entry of it? I would, but alas don't like Vodka.

I support the idea of continuing this inquiry for the pure good of mankind and the accumulation of knowledge. I would furthermore volunteer to conduct further conduct on the grounds that I do like Vodka (though more recently, a certain shift in taste has occured towards Whiskey). However, lacking any freezing capabilities, no such experiments may be conducted at my facility. To make up for this organizational blunder, I will commit myself to studying the effects of Teachers (tm) on teachers, tonight.

Y.

I agree with Yelback that whiskey is a far better substance for alcoholic experiments than vodka.

However, I am torn between my liking for whiskey and my scientific curiosity. Previous experiments have indicated that the product of the experiment is not fit for human consumption. I will conduct a similar experiment with methylated sport. While high in alcohol content it is also rich in impurities and is not fit for human consumption at any time, so there is no loss to my sensitivities regarding the consumption alcohol.

I must take issue with a statement made earlier that the banning of distilled liquor came about because of the dangers of shattering glass. That can effect can also be achieved when making wine and that is perfectly legal.

The real reason that distilling liquor is illegal is that it deprives the tax collectors from what they think is there due. Distilling is illegal in most countries, with the possible exception of New Zealand I believe.

Donald

I know I'm bumping this again, and that it's pretty old, but I have a good reason. I was both previous H2G2 personalities known as "Researcher 95439" and "Mad Scientist" but due to various problems with memory recall (or lack thereof) and changing email accounts, I have never reclaimed those identities. Therefore, I have a vested interest in actually writing an entry expanding my experiments and hypothesis into possibly a full-blown theory if not corollary hypotheses.

So, consider this "in-progress." Plus, I like to write about things done through the conscientious and rigorous application of the scientific method.

- JD